The issue of whether expert medical opinion given at trial that sexual abuse had occurred has long proven to be a controversial issue. The new case brings into sharper focus difficulties that have been well rehearsed before the Court of Appeal before – for example, in the case of R v KF [ 2007 ] Crim 2787 the Criminal Cases Review Commission referred new medical evidence that showed at least two out of three gynaecological experts at trial had got the assessment of sexual abuse wrong.

On this occasion three out of four of the appellants were similarly referred by the CCRC – and the fourth appellant (S) was an appeal at first instance not requiring the assistance of the Commission. All appellants were conjoined into one hearing as the issues over the paucity of the original expert opinion were a shared feature.

High stakes
Over the years the Royal College of Paediatrics and Child Health have recognised the need to address the varying standards of medical assessment in these cases of alleged sexual abuse. If the evidence is genuine then it is strongly supportive of a child having being subjected to serious sexual abuse but if it is not then this may be strongly indicative depending on other evidence that it is a false allegation and that sexual abuse did not occur.

As a result the stakes could not be higher.

The most recent authoritative guide to such medical assessments is to be found in a paper (An evidence based review of literature on physical signs of child sexual abuse)published in 2008. In the case of S, B, C and R, the court received fresh evidence based upon that guidance and opinion from Dr Mary Pillai and Dr Jean Price. The net result of that evidence was that the evidence deployed against the appellants at trial became neutral.

For example in B the original expert retracted key parts of the evidence given at trial and it was noted that post trial developments in medical knowledge regarding the physical signs of sexual abuse supported that stance being taken. In particular, B demonstrates the danger that has been identified in the guidance of opining that findings are indicative of sexual abuse as opposed to only being supportive. Further that in the absence of other supporting facts or detail such findings might not even be supportive.

As a result in the case of B the fresh evidence was that it was not even possible to say with accuracy that such penetration had occurred.

In C issues centred around the issue of attenuation of the posterior of the hymen as an indicator of sexual abuse. The 2008 guidance considered such evidence relying on assessments of the hymen suffering ‘attenuation’ or ‘rubbing/tearing away’ as not helpful terms.

The fresh experts concluded that the evidence of the original expert as to her conclusions was undermined by the new guidance and knowledge but also some of the conclusions reached by the original expert were not even supported by the examination which did take place.

In S the evidence concentrated on that regular feature in cases where an expert concludes something penetrated the complainant’s genitalia but the evidence is nonspecific as to what. The evidence given by the expert at trial was contradicted by fresh evidence and what was said at trial to be hymeneal damage was said to not now be generally accepted as a sign of sexual abuse.

Even had it been the case that distortions were said to have been caused by trauma then a follow up examination should have occurred to check tissue recovery to test that theory.

It should also be noted that there has been considerable criticism over how the examinations take place which can effect conclusions avoiding the ‘frog leg’ examination method in favour of a ‘supine’ or ‘prone’ position. This was a feature in the earlier appeal of KF which stressed the wrong positioning of a child can lead to erroneous results.

Similar concerns arose in the case of R although due to other factors not related to the medical assessment R’s convictions were not quashed.

Significantly in this case the Court of Appeal took the view in relation to three of these appellants that even if the medical evidence only touched on specific counts or complainants that contrary to the Crown’s arguments this would operate to undermine the safety of the remaining counts.

As counsel for S, Mark Barlow noted: ‘The medical evidence at trial shone like a beacon.’

Once the jury accepted that medical evidence it was likely to cement in their view the reliability of the complainants account and that in turn would also fortify their view so far as any other complainant is concerned.

Evidence of sexual abuse on any view is the most powerful evidence before a jury and the court was right to conclude that where it does not stand up to scrutiny then the consequences of it must be to fatally damage the safety of any convictions.

Need for vigilance
What then are the lessons to be learnt from these cases?

That what may appear strong medical evidence of abuse may not amount to evidence of abuse at all

That a careful evidential approach to such allegations is required and that where other supporting features are absent such evidence should be subject to the most careful scrutiny

That medical experts must approach such assessments with great care and ensure they fully comply with the up-to-date guidance to ensure a fair and accurate assessment takes place

These cases once again demonstrate the dangers of sexual allegations leading to miscarriage and the need for greater vigilance in the scrutiny of evidence said to support such allegations. The stakes remain high and genuine evidence of sexual abuse will strongly support a conviction but wrongly presented evidence should never lead to that outcome.